Method of manufacturing tires



Patented Nov. 6, 1928.

UNITED `STATI-:s

1,690,240 PATENT OFFICE.

THOMAS NOBCROSS, OF EBDINGTON, ENGLAND, ASSIGNOR TO DUNLOP TIRE AND RUB BER CORPORATION OF AMERICA, OF BUFFALO, NEW YORK, A CORPORATION 0F NEW YORK.

METHOD OF MANUFACTURING TIRES.

Original application tied August 26, 1825, Serial No. 52,499, and in Great Britain August 27, 1924.

Divided and this application led April 2B, 1926. Serial No. 105,045.

In an application Serial No. 52,499, filed August 26, 1925, I have described an improved form of cushiontire and the method `of making the same. This application is a division of said prior application and is directed to the improved method.

The invention will be understood from the following specification when read in connection with the accompanying drawings in which- Fig. 1 is a cross-section of a tire made in accordance with my method;

Figs. 2 and 3. are part sections showing steps in making a tire according to my method; and

Figs. 4 and 5 are similar sections illustrating the use of a modified form of spacer ring.

According to the invention I provide a rubber tire l having a central cavity 3 therein with a continuous or transversely split spacer ring or segments thereof made of soft iron or other ductile metal or other suitable material.

Grooves, whichv are preferably undercut, are formed in the inner sides of the metal base bands, and the spacer ri .0' or the segments` thereof are provided wit either continuous projections or a series of projections or are otherwise so shaped that they are adapted to it into the said grooves.

When the said spacer ring is, or the segments thereof are, fitted in position with the edges in the ooves formed in the edges of the base ban s, pressure is applied to force the said bands towards each other when the metal of which the projections' or otherwise shaped edges are formed is caused to flow and fill the grooves, thereby firmly holding the base bands at a predetermined distance from each other.

The spacer ring A as shown in section in Fig. 1 is in the form of a transversely split ring which is provided with suitable pro]ections B on each side which are adapted to enter into undercut grooves C formed in the adjacent inner sides of the base bands 2. The spacer ring A is made of soft iron or other ductile metal or other suitable material so that after it has been placed in position between the two bands 2, the metal forming the projections B is caused to fiow and .fill the undercut grooves C by the applicatlon of suitable pressure applied either manually or by a mechanical or hydraulic power press or t e hke to force the bands towards each other.

Fiv. 2 shows a spacer ring A as machined andl iig. 3 shows the same ring after being subjected to pressure between the two bands 2 whereby the projections B have been distorted and forced 1nto the grooves C in the base bands 2.

The grooves C may be of any suitable shape but preferably they are provided with an undercut edge or edges so that the bands 2 are securely locked together on the application of lateral pressure, (i. e., pressure exerted in the direction of the axis of rotation of the tire) and the projections B although preferably continuous throughout each edge of the rin A may be cut away at intervals to reduce t e pressure necessary to force them into the grooves.

The projection B on the spacer ring may be of any suitable shape to enter the groove in the bands 2 and upon the application of lateral pressure thereto to permit of such distortion of the projections that they will lock with the undercut C in the bands 2.

Instead of the continuous spacer ring A I may use a series of segments spaced preferably at regular intervals throughout the circumference of the bands 2, such segments being of the same material and of the same section as that of the ring A.

While I have described in detail the specific embodiments of the invention illustrated, it is not to be construed that I am limited thereto as various modifications or substitution of equivalents may be made without departin from the scope of the invention as define in the appended claims.

What I clailn is 1. In the manufacture of cushion tires, the method which consists of providing a rubber body with a central cavity therein with grooved base bands secured adjacent the cavity, inserting a ductile spacer ring between said base bands, and applying a ressure against the peripheral edge of at east one of said base bands to force them toward each other and thereby upset the edges of the spacer ring within said grooves.

2. In the manufacture of cushion tires, the method which consists in providing a rubber body with grooved base bands secured thereto having undercut grooves formed in their opposed edges, inserting a spacer ring inserting a spacer ring between said base 10 between said bands which is formed with bands, and interlocking the base bands with ductile portionsadapted to enter said grooves, the spacer ring by the application of pres and applying a lateral pressure to upset the sure against the peripheral edge of at least 5 ductileportions of the spacer ring within said one of said base bands.

undercut grooves. In witness whereof, I have hereunto signed 15 3. In the manufacture of cushion tires, the my name.

method which consists in providing a rubl ber body with base bands secured thereto, THOMAS NORCROSS. 

